High data-rate wireless communications at 60 GHz set stringent phase noise (PN) requirements on local oscillators (LOs). Furthermore, LOs require a wide tuning range (TR) to cover the specified frequency bands (e.g., 57 to 66 GHz) with margin for process, voltage and temperature (PVT) variations. Meanwhile, long battery lifetime calls for high power efficiency thus, ultimately, high figure-of-merit (FoM). Unfortunately, CMOS implementations of such 60 GHz LOs suffer from poor PN, limited TR and high power consumption.
There is thus a need for an oscillator that is able to operate at high frequencies in the 60 GHz range that is power efficient, exhibits low phase noise and has a wide enough tuning range to meet the strict requirements of wireless standards with sufficient margin while abiding by the process technology reliability rules.